1. Field of the Invention
The present invention relates to a heat dissipating assembly for electronic components mounted on computer circuit boards, and particularly to a heat dissipating assembly having thermal plates.
2. Description of the Related Art
A computer circuit board typically has one or more heat-generating electronic devices fixed thereon. The circuit board is often installed in a cramped location inside a computer enclosure. In this environment, there is not enough space to install a conventional bulky heat sink onto any electronic device. Instead, a thermal plate can be attached onto a surface of the electronic device. The low profile of the thermal plate allows it to be accommodated in the limited space inside the computer enclosure.
When there is more than one heat-generating electronic device, a single thermal plate attached to all the electronic devices is most convenient. The electronic devices generally have varying heights. Therefore a configuration of the thermal plate must be tailored to the electronic devices of a particular application, in order to ensure that the thermal plate fits all the electronic devices well. This requires unduly high precision machining, and is time consuming and costly. In addition, a single thermal plate may not provide sufficient heat dissipation in certain applications; for example when the electronic devices generate copious amounts of heat, or when the overall configuration of the circuit board limits the coverage of the thermal plate. A second thermal plate may be attached to an opposite side of the circuit board, but establishing thermal connection between the electronic devices and the second thermal plate is problematic.
Accordingly, an object of the present invention is to provide a heat dissipating assembly requiring relatively low precision machining.
To achieve the above object, a heat dissipating assembly in accordance with a preferred embodiment of the present invention for electronic components mounted on a circuit board comprises a first thermal plate, a second thermal plate, a copper adjusting screw and four fastening screws. The first thermal plate forms a plurality of offset portions and thereby defines a plurality of recesses at the offset portions respectively. Depths of the recesses correspond to heights of the electronic components. The first thermal plate and the second thermal plate respectively define four second holes and four fourth holes in respective corners thereof. The fastening screws are extended through the second and fourth holes, thereby securing the first and second thermal plates to opposite sides of the circuit board respectively. The first thermal plate and the second thermal plate respectively define a first hole and a third hole movably receiving the adjusting screw therein. The adjusting screw is tightened so that it improves thermal contact between the offset portions and the electronic components. Because the adjusting screw is made of highly heat conductive material, heat in the first thermal plate is conducted to the second thermal plate through the adjusting screw.